P5 Flashcards
which way do waves transfer energy
in the direction they are travelling
amplitude of a wave
the displacement from the rest position to a crest or trough
wavelength of a wave
the length of a full cycle of the wave
frequency of a wave
number of complete waves or cycles passing a certain point per second
period of a wave
number of seconds it takes for one full cycle
what are transverse waves
vibrations are perpendicular to the direction the wave travel
examples of transverse waves
- all electromagnetic waves
- S waves
- ripples and waves in water
what can transverse waves travel in
on surface of a liquid but not through liquids
what are longitudinal waves
vibrations are parallel to direction the wave travel
examples of longitudinal waves
- P waves
- sound waves
how to measure speed of sound
oscilloscope
how to measure speed, frequency and wavelength
a ripple tank
how to measure frequency
cork and stop watch
- how many times cork bobs over a ripple in a certain amount of time
how to measure wavelength
strobe light
- card with cm^2 behind tank
- turn on strobe light (waves freeze)
- measure distance certain amount of waves cover
- divide by number of waves
how to measure wave speed
pencil and stopwatch
- paper next to tank
- track a wave with pencil for a duration of time
- calculate by measuring line and using time taken
what do waves do at boundaries
absorb
transmit
reflect
rule for reflected waves
angle of incidence = angle of reflection
what is refraction
when light bends
what happens when a wave crosses a boundary between materials
changes speed
the greater the change in speed the more it what
bends
if wave slows down
bends towards the normal
if wave speeds up
bends away from normal
sound waves travel ___ in denser materials
faster
EM waves travel ___ in denser materials
slower
